The Scientific Core has three major components: 1) Cell cultures; 2) Animals; and 3) Microscopy. The Core will assist each of the projects by providing reagents and support services. These include characterized cells, breeding and genotyping of mouse models, microscopy, in situ immunofluorescence imaging and histology. Scientific and technical support includes: 1. Routine isolation and maintenance of primary fetal rat calvarial derive osteoblasts, marrow cells and calvarial osteoblasts from transgenic/knock in mice as needed; 2. Maintenance of various osseous and non osseous cell lines and cell lines with transgenes; 3. Monitoring growth and differentiation parameters to characterize cell lines generated from the projects; 4.Preparation and sterility testing of cell culture media, screening of serum lots and enzyme reagents to ensure uniformity of cultures; 5.Maintenance of knock in/transgenic mouse colonies as required for all three projects. This will include breeding, tagging, and identifying positive and negative mice by Southern blot or PCR analysis; 6.Routine preparation of embryos or tissues for phenotype characterization, which may include either whole embryo P Gal staining, frozen, plastic or paraffin embedding, sectioning and staining; 7.Preparation of total cellular RNA and nuclear matrix proteins from tissues and cell lines; 8.Technical support and training for microscopy, as well as daily assistance with software and hardware aspects specific to the need of each project; 9.Characterization and quality control of all antibodies used for in situ immunofluorescence and; 10.Maintenance of software applications for quantitative procedures to characterize distribution of wild type and mutant Runx2 transcription factors and their co regulatory proteins.